In Patent Literature 1, there is disclosed a wireless audio system, which includes a plurality of wireless speakers grouped into a plurality of groups, and is capable of playing back music data that is different for each group. In the wireless audio system, for each group, the plurality of wireless speakers belonging to the group perform arbitration to select one wireless speaker from among those wireless speakers. Then, the selected wireless speaker serves as a group leader to receive from a user an operation for the plurality of wireless speakers belonging to the same group and transmit a control signal to those wireless speakers. With this wireless audio system, for example, when a plurality of wireless speakers are installed in a plurality of rooms, and the wireless speakers installed in the same room are set as belonging to the same group, music data that is different for each room can be played back.
Incidentally, an output characteristic (including volume level, acoustic characteristic, and sound field effect) of a playback signal of music data is generally set to a suitable output characteristic by a user via an audio controller. In this case, how the music data output from a speaker sounds like depends on a usage environment of the speaker including a size of a room in which the speaker is installed and an installation position of the speaker in the room. This requires the user to search for a suitable output characteristic while listening to the music data output from the speaker. In particular, with the wireless audio system described in Patent Literature 1, the usage environment of the speaker is different for each group. This requires the user to search for a suitable output characteristic for each group, which is troublesome.
Meanwhile, in Patent Literature 2, there is disclosed an acoustic device capable of automatically selecting and applying an acoustic (frequency) characteristic optimum for the usage environment of a speaker. In this acoustic device, a test signal is output from a speaker for each channel and collected by a microphone. Then, the collected sound data is analyzed for each frequency, and an optimum acoustic characteristic is selected from results of the analysis for each channel.